Hi. I made a new topic about my version of Mark's p089zb filter, as per his request so i can provide support for this version.
I went the smd route for several reasons. First one is constant reduction of trough hole component stock/manufacturing, in this case current sense resistor needed for marks original design. Smd version is plentiful and can be found below. Another reason is, while the original design is small, you can always benefit from smaller footprint. And third one is that i am one of those ocd guys that like to have components looking as perfect as they can be, and this one hits that spot for me personally, compact, all traces are same width, almost the same length, while at the original i had the beef with, due to layout it had to be narrower at two points, and tracks are uneven length and unnecessary long (i don't think it matters much for circuit design, but i like things as tidy as possible).
I have kept two components trough hole, inductor and capacitors as those are usually still plenty available, and i'm nowhere near Mark's knowledge to do complex calculations that he has done to go smd inductor route. And those two components are critical. The rest are 1 to 1 replacements, and i chose them to be as big footprint as possible for manual soldering (i haven't used my hotplate for this to make sure it is easy to hand solder). Diode is direct replacement from the same manufacturer, only in smd package. Smallest component is in 1206 package which is a plenty large footprint smd component.
Component list (mouser):
I have trialed it in my b1k nutube preamp, works as nice as the original design. In attachment are mounting hole version and smaller one without mounting holes if someone needs even less of a footprint. Mounting hole version i have increased to 2mm more in length so larger head screw can be used. You can see the size comparison as well.
I went the smd route for several reasons. First one is constant reduction of trough hole component stock/manufacturing, in this case current sense resistor needed for marks original design. Smd version is plentiful and can be found below. Another reason is, while the original design is small, you can always benefit from smaller footprint. And third one is that i am one of those ocd guys that like to have components looking as perfect as they can be, and this one hits that spot for me personally, compact, all traces are same width, almost the same length, while at the original i had the beef with, due to layout it had to be narrower at two points, and tracks are uneven length and unnecessary long (i don't think it matters much for circuit design, but i like things as tidy as possible).
I have kept two components trough hole, inductor and capacitors as those are usually still plenty available, and i'm nowhere near Mark's knowledge to do complex calculations that he has done to go smd inductor route. And those two components are critical. The rest are 1 to 1 replacements, and i chose them to be as big footprint as possible for manual soldering (i haven't used my hotplate for this to make sure it is easy to hand solder). Diode is direct replacement from the same manufacturer, only in smd package. Smallest component is in 1206 package which is a plenty large footprint smd component.
Component list (mouser):
71-WSL2512R0400FEA current sense resistor 0.04R 2512 smd package
71-CRCW1206953RFKEAC 953R resistor 1206 smd
576-TPSMB68A tvs diode DO-214AA-2 smd package
647-UHW1H471MPD 470uf 50v capacitor LS5mm D10mm TH (these are recomended, but can be replaced with any low esr capacitor that fits the footprint and values)
652-RLB0912-2R2ML 2.2uH 7.5A 0.10R inductor,LS 5mm and Diam 9mmI have trialed it in my b1k nutube preamp, works as nice as the original design. In attachment are mounting hole version and smaller one without mounting holes if someone needs even less of a footprint. Mounting hole version i have increased to 2mm more in length so larger head screw can be used. You can see the size comparison as well.
Attachments
@PKI @peppennino @A Jedi there was interest in original thread, and here it is made and tested. I have only 4 more board i can send out, but might be cheaper to order on jlcpcb with shipping prices these days.
Very nice boards! I think I have enough of the TH current sense resistors to take care of my projects (and I have a bunch of boards) so I'm good for now. If the needs arises for smd, I will let you know.
Build for a forum member, for more current needs. Still tiny 😎
